Answer:
Step-by-step explanation:
x² - 12x + a = (x + b)²
x² - 12x + a = x² + 2xb + b²
-12 = 2b and a = b²
b = -6
a = b² = 36
It is quite simple actually since it is simple division with the negative rules.
Just simplify the problem and use the negatives to determine if it is positive or negative. (two negatives equal a positive and one negative equals a negative)
The Answer to your problem is:
0.666667
